Deployment by Module or Application

You can deploy applications or individual modules that are independent
of applications; see About Modules and About Applications. Individual module-based deployment is preferable when
components need to be accessed by:

Other modules

Java EE applications

Application clients (Module-based deployment allows
shared access to a bean from an application client, a servlet, or
an EJB component.)

Modules can be combined into an EAR file and then deployed as
a single module. This is similar to deploying the modules of the EAR
independently.